Cited research: Glob. Biogeochem. Cycles doi:10.1029/2008GB003354 (2010)

Wetlands such as bogs and rice paddies are the largest single source of methane — a potent greenhouse gas — emitted into the atmosphere. Researchers have found that fluctuations in regional and global methane budgets are attributable mainly to weather- and climate-driven changes in the area covered by wetlands worldwide.

Bruno Ringeval at the Laboratory of Climate and Environmental Sciences in Gif-sur-Yvette, France, and his colleagues combined monthly satellite observations of flooded land area with models of global vegetation and methane emissions from wetlands. They found that, in some years between 1993 and 2000, year-to-year variations in wetland extent account for up to 90% of variability in tropical methane emissions. The findings could help to improve models of shifting methane emissions.